Prepare the necessary dishes, containers dried with paper towels, and fill with the required amount of food. Preheat the oven.
In a deep plate, mix all the dry ingredients, namely flour, cocoa, sugar, baking powder and salt. Mix everything thoroughly until smooth.
In a separate bowl, beat the eggs with sugar until the mixture turns white and increases in size. Add the dry mixture in small portions, stirring constantly and avoiding the formation of lumps.
Pour the resulting mixture onto a baking sheet greased with butter and place in an oven preheated to 180℃ and bake the biscuit for 10-12 minutes.
Remove the finished sponge cake from the oven and turn the uncovered side over onto parchment paper sprinkled with cocoa powder. Carefully peel off the top layer of baking paper. Roll it into an even roll and leave to cool.
Break up the chocolate and place it in a bowl set over a pan of water to create a steam bath. When the chocolate starts to melt, add 90 ml of heavy cream and mix everything thoroughly until smooth.
Remove the chocolate from the heat and add the remaining 180ml cream. Mix slowly and carefully. Unroll the roll and grease its surface evenly, then roll it back. You can also grease it on top if you wish. Sprinkle the roll with unsweetened cocoa.
To beautifully serve this chocolate roll, you can use almost anything: fruits, berries, confectionery powder, nuts, coconut flakes - it all depends on your taste preferences and desire to create.